Greenhouse

ABSTRACT

A greenhouse for growing plants in desertic areas, including a watering system for recuperating condensate water from morning and evening dews and feeding this collected water to the plants.

FIELD OF THE INVENTION

This invention relates to greenhouses for growing plants and, morespecifically, to a greenhouse designed for desertic or semi-aridcountries.

BACKGROUND OF THE INVENTION

Conventional greenhouses consist of ground-standing transparent shellbuildings designed for inter alia growing plants in unfavorable weatherconditions, while still providing natural light to the plants. Thesesimple greenhouses are acceptable in countries where the climate isnormally mild and temperatures moderate; however, they areunsatisfactory in harsher climates, because of temperature controlproblems, light intensity and, most importantly, control ofevaporation/watering of the plants. Of course, one can build opaque,insulated greenhouses to eliminate these problems, where light must beartificially produced; but then, the cost factor becomes a majorconsideration.

In the prior art, improved greenhouses have been proposed, to counter atleast some of the above problems. For exemple, in U.S. Pat. No.3,315,409, issued in 1967 to Poulin, there is disclosed a greenhouse forgrowing plants, including two semi-spherical transparent shells 1-2 anda well 4 at the apex thereof. The well 4 is provided with float valves3, closing circular perforations 4.31 pierced therein. Water depositedby rain in the wall 4 is admitted into the greenhouse when the waterlevel rises sufficiently in the well to buoy the float valves 3, so asto water plants therebelow. It also includes heat evacuation means 5,about well 4.

This watering means 3-4 of Poulin is operative only in areas whererainfalls are substantial and occur regularly and, accordingly, wouldnot be suitable for desertic regions where rainfalls are extremelyscarce. Moreover, because the shells 1-2 are both transparent, theplants grown in the greenhouse will have to be limited in their variety,since a great number of plant species cannot withstand the high level ofillumination and/or heat (not-withstanding heat evacuation means 5,which does not induce air circulation in the greenhouse) generated bysunrays in desertic countries.

None of the known prior art greenhouses meet the challenge of beingadapted to grow plants in desertic or at least semi-arid regions.

OBJECTS OF THE INVENTION

The gist of the present invention is to provide a greenhousespecifically adapted for growing plants in desertic or semi-aridregions.

An important object of the above invention is to provide a wateringsystem for such a greenhouse which operates solely by recuperation ofmorning and evening dew.

Another object of the invention is that the above watering system beautomatically operated without the need for pumping means.

Another important object of the invention is to provide means to controlilluminating levels in the greenhouse.

Still another object of the invention is to provide means forautomatically controlling the temperature within the greenhouse.

A further object of the invention is the simplicity and economy ofmanufacture of the greenhouse.

SUMMARY OF THE INVENTION

In a greenhouse for growing plants in desertic or semi-deserticclimates, a dome-shaped rigid opaque shell adapted to stand on theground, a plurality of windows mounted into apertures in said shell andeach defining a transparent pane, an opening at the apex of said shell;a rigid container closing said opening and fixedly secured to saidshell, said container defining a flooring and an upwardly-inclinedcircular side wall, said container adapted to receive a load ofimpervious rocks; a shell door for access to said greenhouse; collectingmeans to recuperate condensate water on said rocks from morning andevening dews; and distribution means for watering said plants with thewater recuperated from dew by said collecting means.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevation of a greenhouse according to a preferredembodiment of the invention and showing the trench in the ground indotted lines;

FIG. 2 is a sectional elevation of the greenhouse taken along line 2--2of FIG. 1;

FIG. 3 is an enlarged view of the section within the area in circle 3 ofFIG. 2;

FIG. 4 is an enlarged view of the section within the area in circle 4 ofFIG. 2;

FIG. 5 is a sectional view taken along line 5--5 of FIG. 4;

FIG. 6 is an enlarged plan view of the exterior face of a firstembodiment of porthole, with its associated greenhouse main wallportion;

FIG. 7, on the fourth sheet of drawings, is a horizontal sectional viewon a slightly-enlarged scale, of the greenhouse, taken along line 7--7of FIG. 1;

FIG. 8, on the third sheet of drawings, is a horizontal sectional view,on an enlarged scale, of the greenhouse top well, taken along line 8--8of FIG. 1, but with the rocks removed;

FIG. 9 is a sectional view of the first embodiment of porthole, takenalong line 9--9 of FIG. 6;

FIG. 9a, on the second sheet of drawings, is the view of FIG. 9 but fora second embodiment of porthole;

FIG. 10 is a sectional view, on an enlarged scale, of the top well,taken along line 10--10 of FIG. 8; and

FIGS. 11 to 13 are enlarged sectional views of the greenhouse bottomwater circulating tubes, taken along lines 11--11, 12--12, and 13--13,respectively, of FIG. 7, and on an enlarged scale relative thereto.

DETAILED DESCRIPTION OF THE INVENTION

As shown in FIGS. 1-4 and 10, greenhouse 20 consists of a substantiallysemi-spherical shell 22, pierced by a plurality of circular apertures24, each aperture 24 being closed by a circular window or porthole 6.The shell 22 is sturdy, rigid and opaque, and preferably, molded fromglass fiber-reinforced resin. Shell 22 is made of a number of successivesectors 22', 22", 22'", see FIGS. 5, 7, which define inturned flanges 25at their side edges. Enlarged portions 25A of the flanges 25 are fixedlyinterconnected in pairs by a plurality of spaced rust-proof bolts 26 andlocking nuts 27. A sealing strip 23 separates each pair of adjacentflanges 25A. Each porthole 6 is closed by a transparent rigid sheet,preferably from a plastic material. The apex portion of the shell 22defines a large circular opening 28. A dish-shaped container 30 ismounted into this opening 28. Container 30, made also of glassfiber-reinforced resin, includes a central floor 32, of concavo-convexshape with the convex side on the exterior. Container 30 also defines anannular side wall 34, which is upwardly outwardly inclined, and aperipheral annular flange 36, which is downwardly inwardly inclined.Walls 32, 34, 36 are each about the same thickness as shell 22. Flange36 conforms to the shape of, and is fixedly secured to, the outer faceof the top annular portion 22A of shell 22 by a plurality of rust-proofbolts 38 and nuts 40. The radius of curvature of the concavo-convex dishflooring 32 is slightly greater than that of the adjacent shell portion22A. Also, a plurality of radially-extending, spaced partition walls 41,see FIG. 8, are mounted on the exterior face of flooring 32, to define aplurality of compartments therebetween for equal distribution therein ofmedium-sized rocks R, for a purpose later set forth. The top edge ofpartitions 41, at 41A, is straight and connects one flange portion 36.The radially-inward ends of partitions 41 extend short of one another,defining a central free space F, also adapted to receive rocks R.

Greenhouse 20 is designed to stand on the ground G. More particularly,earth E is dug from the ground for about a meter or so in depth and foran area slightly larger than the diameter of the greenhouse, toconstitute a trench T. Gravel and/or sand S is poured into the trench T,up to the ground level G. The circular bottom end 22B of shell 22 isthereafter engaged into the gravel/sand base S, down to slightly belowthe ground level G. Less than a meter thick of peat moss M is then addedabove base S, within the shell bottom end 22B, and is designed toconstitute both a substrate and a nutrient supply for plants P. Thelowermost layer of windows 6 should be at the least about one meterabove the ground level G, as illustrated, i.e. above the top of thegrown plants P, for allowing sun-rays to illuminate and heat same. Adoor 42 is also provided at a lower portion of shell 22 for access tothe inside of the greenhouse. Door 42 may include hinges, a knob andlocking bars, not shown.

A large annular plate 44 is welded at W to the shell bottom end 22B.Plate 44 projects radially inwardly of shell 22, at 44A, and includes anumber of bores 44B for loose engagement by bolts 46 locked in place bytop nuts 48. Bolts 46 define a Y-shaped outer bottom end portion 46A,engaging into the gravel/sand base S to therefore constitute anchoringmeans of the shell 22 into the gravel/sand base.

Windows 6 are of either of two types. A small number of them look likethe embodiment shown in FIGS. 6 and 9, and will be more particularlydenoted 6A. Each window 6A defines a peripheral annular frame 52, anintermediate annular sash 54 of dumbbell-shaped cross-section, and acircular transparent plastic pane 56. Sash 54 is made of elastomericsealing material, such as rubber.

Rigid frame 52 is of cross-sectionally L-shape, which mates with acorrespondingly-shaped peripheral contour of aperture 24. Each aperture24 thus defines an inner radially-enlarged aperture portion 24A. Theframe 52 is releasably locked to shell 22 by a few inturned wing-headedbolts 58. Windows 6A can be removed by unscrewing bolts 58 forventilating the greenhouse 20.

The second embodiment of windows 6, at 6B, which make up the bulk ofwindows 6, is shown in FIG. 9a. The difference between portholes 6A and6B is that the latter type is permanently fixed to shell 22. Therefore,there is no need for wing-headed bolts 58 and for the window frame 52,whereby the corresponding window aperture 24' is of uniform diameter andsealing sash 54 directly engages aperture 24'.

The sun moving relative to the greenhouse, each given plant will beilluminated only for a limited time period, since the light rays mustpass through the few registering relatively small windows 6, which areonly temporarily axially registering with the sun rays.

Reference is now made to the watering system shown more specifically inFIGS. 3, 4, 7, and 11-13. A number of flexible tubes 62 are frictionallymounted at their top ends 62A within spaced bores 64, which aresuccessively extending along the bottom end portion of side wall 34 ofdish 30. Tubes 62 run downwardly against the interior face of shell 22,and each is secured thereto at spaced intervals by U-bands 65, which arefixed to shell 22 by bolts 66 and nuts 68. The lower end of each tube 62sealingly engages a diametrally larger elbow coupler 70, the latterembedded in part into peat moss M. An array of horizontal tubes 72A,72B, at right angle with one another, extend through peat moss M, eachend of each of which sealingly engages in the end of elbow coupler 70. Anumber of upright nozzles 74 are welded, or otherwise secured at 76, atspaced intervals to horizontal tubes 72A, 72B, projecting outwardly frompeat moss M amongst plants P. Tubes 72A-B are preferably all inclineddownwardly toward the center of dome-shaped shell 22, whereby each suchtube forms a flat V.

The number of watering tubes 72A, 72B is not critical, although FIG. 7shows five full-length front-to-rear-extending such tubes, but only onefull-length and two segmented transversely-extending such tubes (forclarity of the view). It is understood that any number of full-lengthand/or segmented tubes 72A, 72B is envisioned in accordance withcorresponding number of upwardly-extending tubes 62. Also, a given tube72A or 72B may pass under the corresponding tube 72B or 72A,respectively, provided the one carrying the nozzle 74 at that specificsection is the upwardly-positioned one, see FIG. 12 (both tubes 72A,72B, carry nozzles 74); or alternately, as seen in FIGS. 11 and 13,tubes 72A, 72B may interconnect at their intersection.

The invention is fully operating at sunrise and sunset and, moreparticularly, at morning and evening dews, when variations oftemperature for a given time period is highest, i.e. dT/dt=maximum withT for temperature and t for time. Any substrate surface subjected tohigh variations of temperature is concurrently submitted tocondensation, as is well known. Condensation about the surface of rocksR (which should be of the impervious type) in well 30 will be prevalent,for at least a short duration, thereby generating some water. The waterwill drip on the flooring 32, and will flow along the convex surfacethereof down to its periphery, and thereafter, will flow by gravity intocollecting tubes 62 and into bottom horizontal tubes 72A, 72B. By thetime tubes 72A, 72B, and at least the lower portion of tubes 62, arefull of water, water will start to discharge from nozzles 74 to waterpeat moss M.

Hence, the plants P in the present greenhouse 20 will be watered atleast twice a day, at sunrise and sunset, in automatic gravity-fedfashion, without requiring any pumping mechanism. Also, in the event ofa rainfall, rainwater will be collected by the collecting well 30 anddistributed to plants P via tubes 62 and 72-74, in the same fashion. Anadvantage of the invention is that, since well 30 is well above groundlevel, exterior sand will generally not be able to clog bores 64 and,eventually, nozzles 74, whereby maintenance thereof is reduced to theminimum.

The greenhouse 20 is specifically designed for use in desertic areas.During daytime, the high heat generated by the sunrays should notsubstantially increase the internal temperature of the greenhouse, sincethe main body thereof, or shell 22, is opaque and the constitutingmaterial does have some thermally-insulating properties; the windows 6represent only a small fraction of the total area of the greenhouse,through which the sunrays may pass, for permitting photosynthesis by theplants P. It would accordingly be advantageous that shell 22 be of apale or even white tone, to reduce to the minimum the detrimentaleffects of overexposure to the sun. Similarly, during the night, whichis known to be very cold in the desert comparatively to daytimetemperatures, the fiberglass shell 22 will retain heat within thegreenhouse, and heat losses through the window panes 56 will be limitedto the minimum again because of the relatively low surface thereof inproportion to the whole greenhouse surface.

Should the temperature in the greenhouse 20 exceed an upper thresholdlevel, the wing bolts 58 may be unscrewed to remove at least two windows6A, whereby air ventilation is induced in order to decrease overallinternal temperature. In any event, air circulation at regular daily orso intervals into the greenhouse is necessary for obvious reasons,independent of temperature variations. Again, windows 6A can be removedfor that purpose; a preferred time for such operation could be slightlyafter morning or night dew, when the plants P have been watered by thewatering means of the invention (62-76) and when outside temperature isat a moderate level.

Glassfiber-reinforced resin is preferred for shell 22 and well panel 30,because of its qualities; virtually infinitely resistant to watercorrosion, lightweight, sturdy but having some flexibility in bothstretching and contraction. It is envisioned that film sheets 57 beapplied to window panes 56 to filter ultra-violet and infra-red rays outof light entering the greenhouse. The peat moss M could be any othernutrient-based substrate, including compost and leaf-mould.

An operative greenhouse 20 having the following measurements wassuccessfully assembled: 41/4 meters high, 93/4 meters of diameter, witha well 30 having a 31/2 meters overall diameter and its flooring 32having a 23/4 meters diameter; the load of rocks R supported in well 30being one metric ton; the door 42 measuring about 1 meter by 21/4meters; there being 16 sectors of shell 22; one removable (ventilation)window 6A being provided for each shell sector; each well bore 64 beingabout 5 centimeters in diameter; each window pane 56 measuring about 10centimeters in diameter.

Alternately, vertical tubes 62 could be made of a metallic alloy. Metaltubes 62 would contribute to the reinforcement of well 30, whichsupports up to one ton of rocks, and is accordingly submitted to a veryheavy load which could break the top portion of shell 22 without suchreinforcement.

What I claim is:
 1. In a greenhouse for growing plants, a dome-shapedrigid opaque shell (22), a plurality of windows mounted into aperturesin said shell, and each defining a transparent pane an opening at theapex of the dome shell a rigid container closing said opening andfixedly secured to said shell, said container defining a flooring (32)and an upwardly-inclined circular side wall, said container includingload of impervious rocks; a shell door attached to said shell for accessto said greenhouse; collecting means to recuperate condensate water onsaid rocks from morning and evening dews; and distribution means forwatering said plants with the water recuperated from the dew by saidcollecting means.
 2. A greenhouse as in claim 1, wherein said containerflooring is concavo-convex, with the convex side at the exterior, saidcontainer side wall having a number of bores along its bottom endportion; said collecting means (62-65) including hollow tubes, each onetube opening into a selected one of said bores and running down to theground amongst the plants.
 3. A greenhouse as in claim 2, wherein saidcontainer is dish-shaped, defining a peripheral rim fixedly secured tothe exterior face of said shell said container side wall being upwardly,outwardly inclined, so that said container be funnel-shaped to furtherfacilitate recuperation of rainwater.
 4. A greenhouse as in claim 1,wherein said shell (22) consists of a number of successive sectorpanels, each sector panel defining inturned flanges at their oppositevertical side edges, said flanges of adjacent pairs of sector panelsfixedly interconnected.
 5. A greenhouse as in claim 4, further includingrelease means to remove a window from the shell for thermal control andair circulation in the greenhouse there being at least one window persaid sector pane1, which is equipped with said release means.
 6. Agreenhouse as in claim 5, further comprising sealing members mountedabout said windows and in between said sector panel flanges to preventescape of moisture from the greenhouse when the windows are all closed.7. A greenhouse as in claim 4, wherein the thickness of each said sectorpanel is about thrice that of each window pane.
 8. A greenhouse as inclaim 1, wherein said shell and said container are made ofglassfiber-reinforced resin.
 9. A greenhouse as in claim 1, wherein theratio of diameters of said container to said greenhouse is about 1:3.10. A greenhouse as in claim 3, further including a number of partitionwalls radially extending on the exterior convex face of said containerflooring spacedly one from the other to define therebetweenrock-receiving compartments.
 11. A greenhouse as in claim 10, whereinthe top edge of each of said partition walls is straight, connects toone portion of said peripheral rim but each partition wall (41) extendsshort of the center of said dish-shaped container to further define acentral rock-receiving compartment.
 12. A greenhouse as in claim 1,wherein said transparent window panes are made of plastic material. 13.A greenhouse as in claim 2, wherein said distribution means includes anarray of generally horizontal hollow flexible tubes, each one end ofeach one of which sealingly connected to a corresponding first-mentionedvertical tube via an elbow coupler a plurality of upright nozzlesoperatively connected to said horizontal tubes at spaced intervals; saidnozzles located amongst said plants and adapted for automaticallydispensing water under hydrostatic pressure generated by said collectingmeans.
 14. A greenhouse as in claim 13, wherein said collecting meanstubes and said distribution means tubes are diametrally substantiallyidentical.
 15. A greenhouse as in claim 13, wherein the ratio ofdiameters of one nozzle to one horizontal tube is about 1:3.
 16. Agreenhouse as in claim 13, wherein said horizontal tubes extend at rightangles to and intersect one another.
 17. A greenhouse as in claim 16,wherein at least some of said intersecting horizontal tubes communicateat their intersection.
 18. A greenhouse as in claim 16, wherein saidhorizontal tubes are slightly downwardly inclined toward the center ofsaid greenhouse.
 19. A greenhouse as in claim 4, wherein each shellsector panel includes an inturned flange fixedly secured at its bottomedge (22B), the latter being below ground level; further includinganchoring members each anchoring member anchoring one said sector panelbottom inturned flange to the ground.
 20. A greenhouse as in claim 1,wherein each said window is circular.
 21. A greenhouse as in claim 20,wherein the ratio of diameters of each said circular window to saidshell is about 1:35.
 22. A greenhouse as in claim 20, wherein the ratioof the diameter of each said circular window to the height of said shellis about 1:43.
 23. A greenhouse as in claim 1, with each said windowpane further provided with a film for filtering ultra-violet andinfra-red rays.
 24. A greenhouse as in claim 2, wherein the radius ofcurvature of the concavo-convex flooring of said apex container (30) isslightly greater than that of said shell.
 25. A greenhouse as in claim1, wherein said shell has an exterior light-reflecting colour.